Low-cost laparoscopic simulator - viable way of enabling access to basic laparoscopic training for medical students?

BACKGROUND: Commercial laparoscopic simulators are costly and with limited accessibility. For this reason, medical students very often do not have an easy access to laparoscopic training important for their practical skills development. PATIENTS AND METHODS: Using materials available at a standard hardware store we managed to construct a laparoscopic training box with four eye-hand coordination modules that could substitute commercial solutions. In this work we provide a detailed instructions on creating such a training box. Moreover, to evaluate the functionality of our simulator we conducted a survey of students who were provided training using commercial box trainer and our homemade box trainer. RESULTS: Students considered our homemade laparoscopic training box to be of comparable quality to the commercial solution. All of the surveyed students considered training using a low cost laparoscopic training box to be a positive experience. CONCLUSIONS: Our homemade low cost laparoscopic simulator is relatively easy to construct and was deemed noninferior to the commercial laparoscopic simulator by surveyed students. Such type of laparoscopic simulators could enhance access to laparoscopic training for medical students.

Multicenter Evaluation of the Idylla GeneFusion in Non-Small-Cell Lung Cancer.

Targeted therapy in lung cancer requires the assessment of multiple oncogenic driver alterations, including fusion genes. This retrospective study evaluated the Idylla GeneFusion prototype, an automated and ease-of-use (<2 minutes) test, with a short turnaround time (3 hours) to detect fusions involving ALK, ROS1, RET, and NTRK1/2/3 genes and MET exon 14 skipping. This multicenter study (18 centers) included 313 tissue samples from lung cancer patients with 97 ALK, 44 ROS1, 20 RET, and 5 NTRKs fusions, 32 MET exon 14 skipping, and 115 wild-type samples, previously identified with reference methods (RNA-based next-generation sequencing/fluorescence in situ hybridization/quantitative PCR). Valid results were obtained for 306 cases (98%), overall concordance between Idylla and the reference methods was 89% (273/306); overall sensitivity and specificity were 85% (165/193) and 96% (108/113), respectively. Discordances were observed in 28 samples, where Idylla did not detect the alteration identified by the reference methods; and 5 samples where Idylla identified an alteration not detected by the reference methods. All of the ALK-, ROS1-, and RET-specific fusions and MET exon 14 skipping identified by Idylla GeneFusion were confirmed by reference method. To conclude, Idylla GeneFusion is a clinically valuable test that does not require a specific infrastructure, allowing a rapid result. The absence of alteration or the detection of expression imbalance only requires additional testing by orthogonal methods.

Determining Potassium Bromate in the Inhalable Aerosol Fraction in Workplace Air with Ion Chromatography.

BACKGROUND: The article presents the results of studies performed in order to develop a new method of airborne potassium bromate(V) determination at workplaces. METHODS: The method is based on a collection of the inhalable fraction of potassium bromate(V) using the IOM Sampler, then extraction of bromates with deionized water and chromatographic analysis of the obtained solution. The analysis was performed using ion chromatography with conductometric detection. The tests were performed on a Dionex IonPac®AS22 analytic column (250 × 4 mm, 6 µm) with AG22 precolumn (50 × 4 mm 11 µm). RESULTS: The method provides for potassium bromate(V) determination within the concentration range of 0.043 ÷ 0.88 mg/m3 for an air sample of 0.72 m3 in volume, i.e., 0.1-2 times the exposure limit value as proposed in Poland. The method was validated in accordance with PN-EN 482. The obtained validation data are as follows: measuring range: 3.1-63.4 µg/mL, limit of detection (LOD) = 0.018 µg/mL and limit of quantification (LOQ) = 0.053 µg/mL. The developed method has been tested in the work environment, on laboratory employees having contact with potassium bromate(V). CONCLUSION: The analytical method allowed the determination of the inhalable fraction of airborne potassium bromate(V) at workplaces and can be used to assess occupational exposure.

Transbronchial lung cryobiopsy guided by radial mini-probe endobronchial ultrasound in interstitial lung diseases - a multicenter prospective study.

INTRODUCTION: Transbronchial lung cryobiopsy (TBLC) is commonly used in diagnosing interstitial lung diseases (ILDs). Ageneral anesthesia with endotracheal intubation, balloon blockers and fluoroscopy control is the most common modality. Simplifying the procedure without decreasing it's safety could result in wider use. Prospective, observational study was conducted in three Polish pulmonology centers to evaluate safety and diagnostic yield of TBLC under conscious sedation, without intubation and bronchial blockers and with radial-EBUS guidance instead of fluoroscopy. MATERIAL AND METHODS: In patients suspected of ILD, in accordance with high resolution computer tomography (HRCT) selected lung segments were examined with radial-EBUS mini probe without aguide sheath. If the lung infiltrations were visible this locations were preferred. If not, specimens were taken from two different segments of the same lobe. Two to five biopsies with freezing time 5-8 seconds were performed. Moreover ultrasound examination was used to avoid injury of lung vessels. RESULTS: From March 2017 to September 2019 - 114 patients (M: 59, F: 55) of mean (SD) age 54 (14) years were included to the study on the basis of medical history and HRCT. Histopathology was conclusive in 90 (79%) patients and included 16 different diagnoses (sarcoidosis, EAA, COP predominantly). 24 inconclusive biopsies of unclassifiable pulmonary fibrosis were followed up. Complications included five cases (4.4%) of pneumothorax requiring achest tube drainage and aminor and moderate bleeding in few cases. There was no need for use of balloon bronchial blockers. CONCLUSIONS: TBLC under conscious sedation guided by radial EBUS mini-probe is novel, reasonable and safe technique for histological diagnosis of ILDs.

Prognosis of Patients With Stages I and II Non-Small Cell Lung Cancer With Nodal Micrometastases.

BACKGROUND: This retrospective study aimed to determine the prognostic significance of immunohistochemically detected occult micrometastases (OM) in mediastinal lymph nodes (LNs) obtained during transcervical extended mediastinal lymphadenectomy of stages I and II non-small cell small cancer (NSCLC) patients before complete surgical resection. METHODS: From January 2007 to June 2011, 75 patients with pathologic stage I NSCLC and 73 patients with pathologic stage II NSCLC underwent transcervical extended mediastinal lymphadenectomy and subsequent radical pulmonary resection. During transcervical extended mediastinal lymphadenectomy, 4,810 mediastinal LNs resected and determined as metastases-free by hematoxylin and eosin staining were immunohistochemically labelled with anticytokeratin and BerEp4 antibodies to detect OM. RESULTS: OM were detected in 9 mediastinal LNs of 7 stage I (9.3%) and in 10 mediastinal LNs of 7 stage II (9.6%) NSCLC patients. Patients with mediastinal LN OM had reduced 5-year disease-free and overall survival (21.4%) compared with stage I (61.8%, p < 0.001) and stage II (47.0%, p < 0.05) patients. Multivariable analysis showed the presence of OM was a significant negative prognostic factor for 5-year overall and disease-free survival rates. CONCLUSIONS: The presence of OM in the mediastinal LNs was associated with decreased total and disease-free survival rates in stages I and II NSCLC patients. Immunohistochemical staining of mediastinal LNs obtained preoperatively improved the accuracy of staging and allowed for the identification of patients with a poorer prognosis.

Elevated Foxp3/CD8 Ratio in Lung Adenocarcinoma Metastatic Lymph Nodes Resected by Transcervical Extended Mediastinal Lymphadenectomy.

A balance between tumor invasion and immune defence system is widely investigated. Objective. The aim of this study was to evaluate lymphocyte phenotype in lymph nodes (LNs) of patients with lung cancer in relation to the presence of metastases. Methods. We investigated 364 LNs resected by transcervical extended mediastinal lymphadenectomy (TEMLA) of 49 patients with squamous cell carcinoma (SCC) or adenocarcinoma (AD) with (A) and without metastases (B). Expression of CD4, CD8, CD25, CTLA-4, and Foxp3 was assessed by immunohistochemical staining. Results. We observed a strong nuclear staining for Foxp3 in lymphocytes and cancer cells and strong membranous/cytoplasmatic reaction for CD4 and CD8, but low for CD25 and CTLA-4. There were significantly higher proportions of CD8+ cells in AD (B) versus AD (A) LNs (80% versus 52.5%, p < 0.05). The Foxp3/CD8 ratio was higher in AD (A) versus AD (B) LNs (0.4 versus 0.25, p < 0.05). No significant differences in the cell markers expression in SCC LNs were found. Conclusion. Significant differences in lymphocyte phenotype in AD may indicate an exceptional biology of this type of lung cancer. TEMLA resected LNs may serve as valuable samples for evaluation of immune status in lung cancer patients.

Residua of thymus in the mediastinum - clinical aspects - cadaveric study.

The main goal of this study was to investigate possible residua of thymic tissue in 100 adult cadavers with no thoracic pathology known before, by dissection of standard locations of thymic tissue in perithyroid, periaortic, peritracheal and retrotracheal spaces, as well as areas located next to the course of phrenic, vagus and left recurrent laryngeal nerves. Thus obtained tissue samples were studied by two pathologists independently. The remnants of the thymic tissue were found in 61 out of 100 specimens studied. It means that residua of ectopic thymic tissue is common, which may have a huge impact on the results of treatment of many diseases i.e. myasthenia gravis in course of thymoma.

Initial Polish experience of Flexible 19 gauge Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration.

INTRODUCTION: EBUS is a well established minimally invasive diagnostic tool for mediastinal and hilar lymphadenopathy. The novel ViziShot Flex 19G needle (Olympus Respiratory America, Redmond, WA, USA) was introduced in 2015 in order to improve loaded scope flexion and to obtain larger tissue samples for analysis. The aims of this study were to assess diagnostic yield of Flex 19G needles and to present endoscopist's feedback about the endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). MATERIAL AND METHODS: The Flex 19G needles were used in patients with hilar and/or mediastinal adenopathy in two Polish pulmonology centers. Cytology smears and cell blocks (CB) were prepared. The prospective analysis was performed due to collected data. RESULTS: Twenty two selected patients with confirmed adenopathy on chest-CT (mean age 58 ± 12) underwent EBUS-TBNA with use of Flex 19G needles. All procedures occurred to be diagnostic for smears (yield 100%). The malignancy was found in 15 cases (68.2%), and benign adenopathy in 7 (31.8%). In 12 of 14 cases of lung cancer (yield 85.7%) CB were diagnostic for immunohistochemical and molecular staining. After puncturing nodes, especially in hilar position not extensive bleeding was observed. Comparing to standard 21/22G EBUS-TBNA endoscopists underlined better flexion of loaded scope and sample adequacy and found non-significant differences in another biopsy details. CONCLUSIONS: The first Polish experience with use of Flex 19G EBUS-TBNA needle occurs to be similar in performance with standard technique with use of 22/21G needles and presents high diagnostic yield for lung cancer diagnostics, especially when preparing CB. A safety profile of the biopsy is acceptable.

The orientation of transcription factor binding site motifs in gene promoter regions: does it matter?

BACKGROUND: Gene expression is to large degree regulated by the specific binding of protein transcription factors to cis-regulatory transcription factor binding sites in gene promoter regions. Despite the identification of hundreds of binding site sequence motifs, the question as to whether motif orientation matters with regard to the gene expression regulation of the respective downstream genes appears surprisingly underinvestigated. RESULTS: We pursued a statistical approach by probing 293 reported non-palindromic transcription factor binding site and ten core promoter motifs in Arabidopsis thaliana for evidence of any relevance of motif orientation based on mapping statistics and effects on the co-regulation of gene expression of the respective downstream genes. Although positional intervals closer to the transcription start site (TSS) were found with increased frequencies of motifs exhibiting orientation preference, a corresponding effect with regard to gene expression regulation as evidenced by increased co-expression of genes harboring the favored orientation in their upstream sequence could not be established. Furthermore, we identified an intrinsic orientational asymmetry of sequence regions close to the TSS as the likely source of the identified motif orientation preferences. By contrast, motif presence irrespective of orientation was found associated with pronounced effects on gene expression co-regulation validating the pursued approach. Inspecting motif pairs revealed statistically preferred orientational arrangements, but no consistent effect with regard to arrangement-dependent gene expression regulation was evident. CONCLUSIONS: Our results suggest that for the motifs considered here, either no specific orientation rendering them functional across all their instances exists with orientational requirements instead depending on gene-locus specific additional factors, or that the binding orientation of transcription factors may generally not be relevant, but rather the event of binding itself.

The efficacy of EGFR gene mutation testing in various samples from non-small cell lung cancer patients: a multicenter retrospective study.

INTRODUCTION: Testing for the epidermal growth factor receptor (EGFR) gene mutations requires considerable multidisciplinary experience of clinicians (for appropriate patient selection), pathologists (for selection of appropriate cytological or histological material) and geneticists (for performing and reporting reliable molecular tests). We present our experience on the efficacy of routine EGFR testing in various types of tumor samples and the frequency of EGFR mutations in a large series of Polish non-small cell lung cancer (NSCLC) patients. METHODS: Deletions in exon 19 and substitution L858R in exon 21 of EGFR gene were assessed using real-time PCR techniques in 1,138 small biopsies or cytological specimens and in 1,312 surgical samples. RESULTS: Out of 2,450 diagnostic samples (containing >10% of tumor cells), the occurrence of EGFR gene mutations was 9%; more frequently in women (13.9%) and adenocarcinoma patients (10%), particularly with accompanying expression of TTF1 (13.0%). The frequency of EGFR gene mutations was similar in cytological and histological specimens, and in primary and metastatic lesions, and did not depend on the percentage of tumor cells and quality of isolated DNA. Cytological or small biopsy, compared to surgical specimens showed lower percentage of tumor cells, with no impact on the quality of real-time PCR assay. CONCLUSION: Cytological and small biopsy samples with low (10-20%) content of tumor cells and specimens from metastatic lesions are a sufficient source for EGFR mutation testing in NSCLC patients. The incidence of EGFR gene mutations in examined population was similar to those reported in other Caucasian populations.

Fast cytological evaluation of lymphatic nodes obtained during transcervical extended mediastinal lymphadenectomy.

OBJECTIVES: Evaluation of the diagnostic efficiency of the intraoperative cytological examination of lymphatic nodes obtained during transcervical extended mediastinal lymphadenectomy (TEMLA). METHODS: All mediastinal nodes obtained during consecutive TEMLA operations in patients with confirmed lung cancer were examined. Cytological imprints from cross sections of nodes were performed, fixed in 96 proof alcohol and stained with Haematoxylin-Eosin. The cytological slides were evaluated by light microscopy intraoperatively, and a standard paraffin histological examination of the same nodes was done afterwards for confirmation of the final diagnosis. RESULTS: Intraoperative cytological studies were performed in 63 patients (17 women and 46 men; overall in 453 mediastinal nodal stations) from 1 April 2009 to 28 February 2011. The mean number of nodes/procedure was 27.8. The mean time of performance of the examination was 37 min, including 7 min for smears, 13 min for staining and 17 min for microscopic examination (overall 37 min). The cytological study discovered neoplasmatic cells in 12 of 63 patients, nodal stations in 22 of 453 and nodes in 44 of 1724. According to the analysis of the 63 patients, the imprint cytology technique had a sensitivity of 92.3%, specificity of 100%, accuracy of 98.4%, positive predictive value of 100% and negative predictive value of 98.0%, as was confirmed by the final histopathological examination. CONCLUSIONS: (i) Cytological imprints examination was characterized by a very high specificity and sensitivity, is technically simpler and faster and allows for the examination of several dozens of lymphatic nodes during a single TEMLA procedure within an acceptable time, and after the exclusion of N2 nodes enables the simultaneous performance of a radical lung resection. (ii) The presented technique was the alternative for the traditional histopathological examination of the material frozen in cryostat.

Ectopic thymic tissue in the mediastinum: limitations for the operative treatment of myasthenia gravis.

OBJECTIVES: The aim of the study was to investigate the distribution of ectopic thymic tissue in the mediastinum and to evaluate the possible relevance of this distribution to the therapeutic yield of thymectomies in patients with myasthenia gravis. METHODS: In this prospective autopsy study, mediastinal dissections were performed on 50 cadavers without any previously known intrathoracic pathology. The initial dissection was performed in the same way as during the maximal thymectomy. The second stage consisted of dissecting areas of fatty tissue located out of reach of the standard maximal thymectomy, such as the perithyroid, periaortic, peritracheal and retrotracheal areas, as well as the areas adjacent to the right and left phrenic and recurrent laryngeal nerves. Each specimen was independently examined by two pathologists for ectopic thymic tissue. RESULTS: There were 41 (82%) male and 9 (18%) female cadavers, with a mean age of 44.3 years (range: 15-75). Ectopic thymic tissue was detected in 32 out of 50 cadavers (64%). In 10 (20%) cadavers thymic foci were found in locations accessible to the standard surgical intervention and in 22 (44%)-in inaccessible locations. Thymic tissue incidence in individual locations was as follows: retrothyroid, 3 (6%); peritracheal, 5 (10%); retrotracheal, 1 (2%); right phrenic nerve, 2 (4%); left phrenic nerve, 14 (28%); right recurrent laryngeal nerve, 2 (4%); left recurrent laryngeal nerve, 2 (4%) and periaortic, 0. CONCLUSIONS: The incidence of ectopic thymic tissue in the mediastinum is common. Although some improvements in the results of thymectomies may be expected with more extensive dissection, the frequent presence of thymic foci in anatomical locations hardly accessible to surgical intervention may be the true limitation for surgical treatment of myasthenia.

Bone turnover markers and bone strength during the first weeks of life in very low birth weight premature infants.

OBJECTIVE: To determine the association between changes in bone turnover markers and bone strength of very low birth weight infants during the first eight postnatal weeks. STUDY DESIGN: Twelve very low birth weight premature infants [mean gestational age: 28.4 +/- 0.6 weeks, mean birth weight: 1131 +/- 62 grams] participated in the study. Bone strength was evaluated weekly by quantitative ultrasound measurements of tibial bone speed of sound (SOS, Sunlight Omnisense). Bone specific alkaline phosphatase (BSAP), a marker of bone formation, and carboxy terminal cross-links telopeptide of type-I collagen (ICTP), a marker of bone resorption, were collected at the ages of one, four and eight weeks. RESULTS: BSAP increased significantly (from 119.9 +/- 16.2 U/L to 132.1 +/- 11.9 U/L and 152.1 +/- 15.7 U/L at one, four and eight weeks of life, respectively, p<0.05). ICTP decreased significantly during the study period (from 122.3 +/- 8.7 ng/ml to 96.0 +/- 4.8 ng/ml and 92.3 +/- 5.4 ng/ml at one, four and eight weeks of life, respectively; p<0.05). There was a significant decrease in bone SOS (from 2886 +/- 29 m/sec to 2792 +/- 30 m/sec and 2753 +/- 30 m/sec at birth, four weeks and eight weeks of life, respectively; p<0.02). There was no correlation between the levels of bone markers and bone SOS. CONCLUSION: In VLBW premature infants, there is a significant decrease in bone strength concomitant with biochemical evidence for new bone formation (increase in BSAP and a decrease in ICTP) during the first eight postnatal weeks. Changes in the biochemical markers could not predict the changes in bone strength.

Early physical activity intervention prevents decrease of bone strength in very low birth weight infants.

OBJECTIVE: To evaluate the effect of early range-of-motion intervention on bone strength and bone turnover in very low birth weight infants. METHODS: Twenty-four infants (mean birth weight: 1135 +/- 247 g; mean gestational age: 28.5 +/- 2.3 weeks) were matched for gestational age and birth weight and then randomly assigned into exercise (n = 12) and control (n = 12) groups. Exercise protocol started at the first week of life and involved daily extension and flexion range of motion against passive resistance of the upper and lower extremities (5 minutes per day, 5 days per week, 4 weeks). Growth parameters, bone strength, and biochemical markers of bone homeostasis were measured at enrollment and after 4 weeks. Bone strength was determined using quantitative ultrasound measurement of bone speed of sound (SOS) at the middle left tibial shaft. RESULTS: Bone SOS decreased significantly in the control group during the study period (from 2892 +/- 30 m/sec to 2799 +/- 26), whereas bone SOS of the exercise group remained stable (2825 +/- 32 m/sec and 2827 +/- 26 m/sec at baseline and 4 weeks, respectively). This significant difference in bone SOS was not expressed in the biochemical markers of bone homeostasis. CONCLUSIONS: There is a significant postnatal decrease in the bone SOS of very low birth weight infants. A brief range-of-motion exercise attenuates the decrease in bone strength and may decrease the risk of osteopenia.